10621
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12320
- Proper Divisor Sum (Aliquot Sum)
- 1699
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9072
- Möbius Function
- -1
- Radical
- 10621
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 55
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n) = (n-1)*n*(n+4)/6.at n=39A005581
- Pseudoprimes to base 6.at n=28A005937
- Pseudoprimes to base 7.at n=18A005938
- Coordination sequence for sigma-CrFe, Position Xd.at n=26A009959
- Differences between two positive cubes in exactly 2 ways.at n=9A014440
- Pseudoprimes to base 42.at n=27A020170
- Pseudoprimes to base 79.at n=41A020207
- Strong pseudoprimes to base 87.at n=14A020313
- Strong pseudoprimes to base 92.at n=22A020318
- Values of Newton-Gregory forward interpolating polynomial (1/3)*(n-1)*(2*n+3)*(2*n-1).at n=20A030440
- Difference between two positive cubes in more than one way.at n=10A034179
- Composite numbers k, not a power of 2, such that the E(k) == 1 (mod k), where E(k) is the k-th Euler number (A000364).at n=32A035163
- Numbers ending with '1' that are the difference of two positive cubes.at n=37A038856
- Numbers that are the sum of two (possibly negative) cubes in at least 2 ways.at n=33A051347
- 10000n+1, 10000n+3, 10000n+7, 10000n+9 are all primes.at n=6A064963
- a(n+4) = floor( ( a(n) + 2*a(n+1) + 3*a(n+2) + 4*a(n+3) )/5 ), with a(0), a(1), a(2), a(3) equal to 0, 1, 2, 3.at n=25A074733
- Number of permutations of length n which avoid the patterns 2341, 3241, 4213.at n=8A116820
- Nonprimes k such that 7^k == 7 (mod k).at n=41A122784
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 1), (0, 1, 1), (1, 0, 1), (1, 1, -1)}.at n=7A150650
- a(n) = 12*n^2 + 18*n + 7.at n=29A154105